1. Field of the Invention
The present invention relates to an improved fastener arrangement for an electrical junction box and, more particularly, to a molded electrical junction box having an improved clip receiving aperture for guiding a clip into the aperture during assembly. The clip is thus used to retain a fastener, such as a screw, that mounts a wall switch or plug.
2. Description of the Prior Art
Electrical junction boxes which enclose and protect the wiring to electrical wall switches and plugs have been used for many years and are required by most, if not all, building and electrical codes. Over the years, many designs have been proposed to improve electrical junction boxes by, for example, devices which permit quick assembly of an electrical switch or plug into the junction box. One such arrangement is shown in U.S. Pat. No. 2,149,719, which issued Mar. 7, 1939, by H. L. Arnest. This device shows a junction box having a screw receiving sleeve and a cylindrical insert therein with spring fingers extending from the cylinder. The spring fingers are tapered to permit the rapid thrust insertion of a screw. The fingers then contract upon the screw to retain it within the sleeve and thereby quickly mount the wall switch or plug. The junction box shown in the Arnest patent is constructed from fabricated metal.
A later development in junction box technology included the use of molds to form a molded junction box. Such a box is shown in U.S. Pat. No. 2,867,349, which issued Jan. 16, 1959, by W. M. Parker, Jr. The junction box taught by this patent is formed from a mold which places molded screw holes at appropriate places in the junction box for receiving and mounting a switch or plug. This device does not account for a quick thrust insertion of a fastening screw by pushing the screw into the threaded hole, as in the Arnest patent.
In U.S. Pat. No. 4,167,648, issued Sept. 11, 1979, by A. C. Lockwood, there is disclosed a molded junction box having molded sidewalls, a closed bottom and open top. The short walls of the four-sided junction box include columns which terminate at the opened top of the junction box and into which are molded specially designed and complex apertures for receiving specially designed clips. The clips accommodate a thrusting insertion of the fastening screws.
Other forms of molded junction boxes have been designed with various apertures molded into the clip receiving columns and various clips for insertion therein. Most of these prior art arrangements disclose an electrical junction box with clip receiving columns having apertures therein that are complex in shape. The complexity of these apertures requires a more complex mold which is difficult to maintain. Further, the process of assembling a clip into an electrical junction box and its complexed aperture is more difficult.